对辊破碎机层压破碎过程的DEM-MBD联合仿真与试验

DEM-MBD co-simulation and experiment on laminating crushing process of roll crusher

通过控制合理的入料粒径能够有效提高对辊破碎机层压破碎效率,但在分析物料破碎过程时存在腔内物料不可视、破碎数据难采集等问题。为了提高对辊破碎机的破碎效率,优化其破碎过程的分析方法,采用离散元法(discrete element method,DEM)与多体动力学(multibody dynamics,MBD)建立联合仿真模型,探究对辊破碎机层压破碎过程中物料的破碎规律;并进行对辊破碎机层压破碎试验,分析不同入料粒径配比时矿石物料的孔隙率对破碎效率的影响,并试验验证联合仿真模型的准确性。结果表明:对辊破碎机的物料破碎由单颗粒破碎和层压破碎组成,破碎过程分为料层密实、物料破碎和结团排料3个阶段;为提高对辊破碎机破碎效率需要控制入料粒径不小于辊隙的40%,在此条件下,通过混入尺寸大小为入料粒径50%~100%的矿石降低物料孔隙率可以提高破碎效率;DEM-MBD联合仿真与试验结果的碎后粒径分布曲线基本吻合,从而验证建立的联合仿真模型的可靠性。

The laminating crushing efficiency of roll crusher can be effectively improved by controlling reasonable feeding grain size,but there are some problems in analyzing the crushing process,such as invisible material in the chamber and difficult to collect crushing data.In order to improve the crushing efficiency of roll crusher and optimize the analysis method of its crushing process,a co-simulation model was established by using discrete element method(DEM)and multibody dynamics(MBD).The crushing law of the material in process of laminating crushing of roll crusher was studied.The lamination crushing test of roll crusher was carried out.The influence of the inlet particle size with different porosity on the crushing efficiency was analyzed and the accuracy of the co-simulation model was verified.The results show that the crushing process of roller crusher consists of single particle crushing and lamination crushing.The crushing process is divided into three stages,compaction of material layer,crushing of material and agglomeration and discharge of material.In order to improve the crushing efficiency of roll crusher,it is necessary to control the feed particle size of not less than 40%of the roll gap.Under this condition,the crushing efficiency can be improved by mixing the ore with the feed particle size of 50%~100%to reduce the porosity.The DEM-MBD co-simulation is in good agreement with the particle size distribution curves of the experimental results,which verifies the reliability of the established co-simulation.